Wire unspooling and braking apparatus



March 3, 1970 P. DEMON 3,498,564

WIRE UNSBOOLING AND BRAKING APPARATUS Filed May 3, 1968' IN VENTORZ PETER DISMON United States Patent 3,498,564 WIRE UNSPOOLING AND BRAKING APPARATUS Peter Dismon, Porselen, Germany, assignor to Glanzstolf AG, Wuppertal, Germany Filed May 3, 1968, Ser. No. 726,364 Claims priority, application Germany, May 9, 1967,

G 50,039 Int. Cl. B65h 49/30, 59/16 US. Cl. 242-128 5 Claims ABSTRACT OF THE DISCLOSURE Apparatus for the overhead withdrawal of wire coiled on a flanged spool for supply to a wire-drawing device in which braking or tensioning elements are provided by a rounded, smooth-surfaced annular guide rail concentrically mounted on the run-off end of the spool and extending radially outwardly of the spool winding below the run-off flange, and an elastomeric, abrasion-resistant collar coaxial with the spool and supported so as to rest on the outer portion of the guide rail such that the wire is pressed or nipped between the collar and the guide rail during its withdrawal outwardly of the spool winding in running and sliding contact around the guide rail and then inwardly over the free run-off end of the spool.

This invention is concerned with an apparatus for the overhead unwinding or unspooling of the feed spool for a wire-drawing device, and more particularly, the invention is directed to novel means for braking or tensioning the wire as it is removed from the spool winding and directed over the free or run-01f end of the spool. The apparatus of the invention results in an improved operation, including a greater velocity of unwinding or unspooling the Wire.

The initial material used for the production of metallic wires, e.g. steel or copper wires, is normally in the form of a wire rod as obtained from a conventional wire rod manufacturing operation. This initial wire rod, which has a relatively large diameter, is brought down to the diameter required for the final product in a so-called wire-drawing machine or device. In order to reduce the diameter of the initial rod or wire, it is drawn through the tapered bore of a wire-drawing die by means of a block or other suitable means to draw the wire. A single die often contains a number of bores which taper in the direction of the wire draw, and the die and drawing block are generally mounted on a bench or other suitable support, the entire assembly being referred to as a wiredrawing frame. In the production of fine wires, several dies or drawing elements can be arranged in sequence so that the wire is successively drawn down to a smaller and smaller diameter. In such continuous wire-drawing devices for fine wire, the principles involved are essentially the same as in a single drawing operation and various means can be employed for the proper drawing or pulling of the wire through the individual tapered bores of the successive dies.

In a fine wire-drawing device, the initial supply of wire is ordinarily withdrawn from a rotatable spool. After the drawing operation is completed, the finished fine wire is taken up again onto a spool or coil former. In order to provide an economical production of the fine wire, it is of course desirable to draw the greatest possible weight of wire per unit time in the wire-drawing device.-

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or velocity and the corresponding amount of wire finished m a unit of time is relatively limited or restricted, primarily due to the great difficulties which arise in starting and stopping the wire-drawing operation. Thus, the strength of the wire as determined by the size of its crosssection often is not sufficient to withstand the tensile load placed on the section of wire between the feed spool and the feed side of the wire-drawing device, particularly when starting up the wire-drawing frame due to the inertia or dead weight of the initially motionless mass of the coiled spool. Thus, even when starting at relatively low drawing speeds, the load required to start the rotation of the feed spool can easily cause the wire to rupture. Also, when stopping the wire-drawing frame, the feed spool tends to continue running either because its mass is only slightly braked or because it is quite diflicult to provide a sufiicient braking Within a reasonable period of time. In this case, an undesired length of wire unwinds from the spool and is not processed on the wire-drawing frame. This excess work material tends to form a tangled convolution or coil of the wire which prevents an immediate renewal of the drawing operation, because this excess length of wire must be disentangled by hand and Wound back onto the feed spool or else removed as waste material.

In order to avoid the disadvantages of a lateral unwinding of the wire from a rotating feed spool, it'has been suggested that the wire be uncoiled over a free end of the spool in a so-called overhead unspooling or unwinding operation. However, even with this overhead unspooling of the wire to be supplied to the wire-drawing operation, it has not been possible to avoid disturbances in the drawing step. Immediately after starting up the wire-drawing frame, disturbances arise because the wire does not unwind as one coil or loop at a time but instead the wire tends to become slack over a number of windings of the outermost coil layer, i.e. such that several turns of the coil become loose and disconnected from the otherwise compact spool winding. These loose turns or windings shift into one another so that their position on the spool no longer corresponds to that which is required for a normal sequential run-off one after the other. This leads to further disturbances in the unwinding of the wire from the feed spool so as to cause very pronounced difficulties in the manufacturing process.

With proportionately small spool dimensions and slow run-off velocities, the main disadvantages of an overhead unwinding can be overcome by the arrangement of so-called flyers, commonly used for unspooling thread in the textile industry. Spools equipped with such flyers make it possible to regulate a desired tension in the wire as it is unwound with the assistance of a braking device. It is then possible to substantially avoid the simultaneous removal or disengagement of several wire turns or coils, and one can be reasonably certain of achieving a run-ofi of the wire from the spool in an operation which is relatively free of disturbances. However, with increasing spool size and run-off velocity, a disturbance-free overhead unspooling of the wire can no longer be accomplished in an economical manner by the use of such flyers.

One object of the present invention is to overcome prior difiiculties in the rapid unspooling of a wire from a flanged feed spool, particularly where the wire is being supplied to a fine wire-drawing frame at relatively high speeds and large quantities.

Another object of the invention is to provide braking means in combination with apparatus for the overhead unwinding of a wire coiled on a feed spool, whereby one can achieve high feed velocities at a uniform or even rate so as to guarantee a disturbance-free operation.

Still another object of the invention is to provide ap paratus for the overhead unspooling and braking of wire from a feed spool which is relatively simple in its con-.

struction and very easy to assembly with a minimum of moving parts.

Yet another object of the invention is to provide an overhead unspooling and braking of the feed spool for a fine wire-drawing device which is durable in its operation and which avoids any substantial deformation or damage to the wire being treated.

These and other objects and advantages of the invention will become more apparent upon consideration of the following detailed specification.

It has now been found, in accordance with the invention, that a very satisfactory and highly improved overhead unspooling of wire cooled on a flanged feed spool can be achieved by providing a braking means arranged on the run-off flange or free end of the feed spool. This braking means essentially includes a rounded, smoothsurfaced circular guide element mounted concentrically on the free end of the spool and extending at least partly past the run-off flange into an annular region which lies radially outwardly of the spool portion on which the wire is coiled, the diameter of this circular guide element being sufficiently greater than the diameter of the runoff flange to permit the wire to be pulled off said spool outwardly around the guide element in running and sliding contact therewith and then inwardly over the free end of the spool, and collar means composed of an elastomeric, abrasion-resistant material coaxial with and supported externally of the spool and resting on the outer portion of the circular guide element for application of a braking pressure on the wire as it runs between the collar means and the circular guide element. The feed spool is preferably attached securely at one end to a base frame while mounting the circular guide element adjacent the run-off flange at the opposite free end of the spool.

In a preferred embodiment, the circular guide element is preferably composed of an annular guide rail sup ported by a plurality of radial spokes or arms extending from a hub fastened axially at the free end of the feed spool. When formed in this manner as a type of spoked wheel, the circular guide element can be tightly connected both with the spool body as well as with the base frame of the apparatus by means of a common bolt or screw which passes through the spool axis into the base frame. Also, the smooth, rounded surfaces of the circular guide element which are in running and sliding contact with the wire are preferably coated with a hard chromium plat ing. The collar or sleeve which provides a braking pressure on the wire during its removal from the feed spool is preferably a molded article composed of a plasticized polyvinyl chloride. The apparatus of the invention is particularly useful in combination with a wire-drawing device having means to pull the wire from the spool winding over the run-off flange to a feed guide point located approximately in the axis of the spool at a spaced distance from the free end thereof.

For a detailed illustration of one preferred embodiment of the apparatus according to the invention, reference is made to the accompanying drawing in which:

FIG. 1 is a partly schematic overall view of a suitable arrangement of the feed spool and braking means according to the invention with a wiredrawing frame;

FIG. 2 is a side elevational view, taken partly in crosssection through the axis of the feed spool and braking means; and

FIG. 3 is an enlarged detail of the braking means taken from FIG. 2.

In the partly schematic illustration of the wire-drawing operation shown in FIG. 1, the coiled wire on the feed spool 1 is run off over the free end of the spool to a fixed guide point 2 and pulled through a conventional die in a wire-drawing frame 3. The feed spool 1 and its braking elements including the collar 4 are connected to and supported by a suitable base frame 5. The position of the spool is relatively unimportant since it is preferably mounted in a non-rotatable, fixed position on the base frame. Thus, the spool may be positioned at an inclined angle as illustrated in FIG. 1 or it can be vertically positioned with reference to its longitudinal axis, preferably'with its free end at the top. In this respect, the term overhead unspooling or the like refers to a withdrawal of the wire over the free end of the spool as distinguished from a lateral or transverse unwinding of the wire tangentially from a rotating spool.

The actual operation of drawing the wire is quite well known and is therefore illustrated generally as the wiredrawing frame 3. It will be understood that the wiredrawing frame may contain one but more often a plurality of tapered bores in a wire-drawing die, so that there will be a series of feed spools for each wire-drawing frame. Also, several frames or dies may be arranged in sequence to gradually draw the wire into a fine diameter in two or more drawing steps or stages. Conventional drawing means are associated with such wire-drawing frames and are not illustrated in detail.

The wire unspooling and braking apparatus associated with the feed spool 1 is shown more fully in FIG. 2 in which various positions of the wire W during its run-off or unspooling are indicated by broken lines. On the base frame or supporting member 5, there is carried the feed spool 1 which consists of an elongated spool sleeve 6, an upper or run-off flange 7 and a lower or supporting flange 8 at the fixed end of the spool, the two flanges serving to retain the wire coil or spool winding 9 on the sleeve of the spool as a firmly wound wire package. Additional reinforcement of the flanges can be provided by means of suitable ribs or struts 7a and 80, respectively.

In order to pull the wire outwardly around the run-off flange 7 and then inwardly over the free end of the spool 1, a circular guide element or annular guide rail 10 is located concentrically around the coiled wire 9 on the spool immediately adjacent the run-01f flange 7. This circular guide element or guide rail 10 must be mounted on the free end of the spool 1 so as to extend at least partly past the run-off flange 7, preferably so that its inner diameter is somewhat greater than the outer diameter of the flange 7.

The means of supporting and mounting the guide rail 10 must be arranged so as to avoid interference with the running wire, and this is most conveniently accomplished by constructing the circular guide element in the form of a wheel with spokes, as illustrated. Thus, the guide rail 10 is connected by means of a number of angled spokes or radial arms 11, which in turn are connected to a central hub member 12 mounted on the free end of the sleeve 6. There are preferably about three to eight radial arms 11 supporting the guide rail 10, and this structure is relatively light in weight while providing suflicient strength and stability to withstand the forces placed thereon by the running wire. The circular guide element or spoked wheel 10 is then firmly seated and secured onto the body of the spool 6 by means of a threaded bolt 13 which can be screwed into the base frame 5. A suitable handle 14 or other means can be provided in order to screw the bolt in place. In this manner, the circular guide element is tightly connected both with the spool body as well as with the base or supporting frame for the feed spool.

As the wire W is withdrawn from the winding 9, it first runs outwardly around the outer circumferential portion of the guide rail 10 and then inwardly to a feed guide point from which it can be supplied to the fine wiredrawing frame as indicated in FIG. 1.

The outer diameter of the circular guide element 10 must be sufficiently large to extend radially of the coiled wire 9 at a distance which prevents contact of the wire with the run-off flange 7 during the overhead unspooling. In this manner, injury to the smooth Wire surfaces by contact of the wire with the unfinished or rough flange 7 is fully prevented. As shown in FIG. 3, it is especially advantageous to provide on the circumferential surface of the main core of the guide rail a over which the wire runs an abrasion-resistant layer or coating 10b in the form of a hard chromium plating. This not only preserves the desired surfaces of the wire itself but also prevents excessive wear of the contacting surfaces of the guide rail.

In order to provide a smooth and trouble-free unspooling of the coiled wire in accordance with the invention, it is essential to provide a braking action on the wire as it is removed from the coil by means of the externally supported collar or sleeve 4. This collar in combination with the guide rail provides a braking means by resting the collar at least tangentially and preferably with a slightly draped contour on the outer circumferential surface of the guide rail 10. Thus, as shown in FIGS. 2 and 3, the lower or free end 4a can be circular in shape and concentric with the spool 1 while the upper or supporting portion 4b of the collar preferably tapers radially inwardly in the same direction as the running wire, thereby providing additional contact surface and a correspondingly greater braking action.

The collar is conveniently supported by means of a steel reinforcing ring worked into its upper supported rim. This reinforced rim 15 rests on a similar supporting ring 16 which is held in place by a plurality of angled legs 17 mounted in suitable sockets 18 on the base frame 5. In general, the weight of the collar 4 and its reinforcing ring 15 is suflicient to hold it in place, but it is also feasible to clamp the rim 15 to the supporting ring 16 or to fasten these members in any other suitable manner. Once the collar is mounted in place, the supporting means is sufficient to prevent the collar from shifting or sliding off of the guide rail 10. The wire is thus subjected to a uniform braking action as it is pinched or nipped between the guide rail 10 and the collar 4.

The collar 4 should be constructed of an elastomeric material which is sufficiently resistant to abrasion in order to remain effective over reasonably long periods of operation. The elasticity of the collar should preferably correspond approximately to that of a rubber employed in vehicular tires or similar natural or synthetic rubbers. However, since the collar is exposed to substantial frictional wear and tear caused by the wire running at a high velocity, ordinary rubber materials may wear out too rapidly so as to be uneconomical. Therefore, it is particularly desirable to employ a collar composed of a synthetic elastomeric polymer which has a high abrasion resistance While retaining a reasonable degree of elasticity or flexibility. For example, especially good results have been achieved by producing the collar from a plasticized polyvinyl chloride molding composition, for example of the type forwhich data is given in the Kunststofftaschenbuch (Plastic Handbook), 16th Edition, 1965, p. 189, Sec. 4.1.4.6. This material possesses the desired elasticity for the collar, does not age and exhibits no noticeable appearance of wear even after a months period of use. The preferred plasticized polyvinyl chloride materials can be readily molded into the desired shape of the collar and provided with sufiicient body and weight as well as elasticity in order to yield the desired braking effect. On the other hand, it is also feasible to use other elastomeric polymers having similar properties or to prepare the collar as a laminated or fabric-reinforced flexible member, provided that the contacting surface is primarily characterized by its elastic and abrasion-resistant properties.

In order to place the feed spool into operation, the completely wound spool 6 with its coiled wire package 9 is placed on the base frame 5, the circular guide element 10 is inserted on top of the spool sleeve 6 and fastened thereon by means of the bolt 13 screwed into the base frame 5. The retaining ring or collar holder 16 can then be mounted around the spool 1 by insertion into the sockets 18 which are preferably permanently fastened to the base frame 5. The collar 4 is then inserted over the spool 1 and around the circular guide element 10 where it is supported by its upper rim 15 resting on ring 16. An initial length of wire from the spool winding is pulled off between the guide rail 10 and the collar 15 and directed into the die of the wire-drawing frame.

As the wire W runs off from the spool, it moves from the outer spool circumference or outer layer of the coil 9 to describe a constantly changing conically tapered path or generated surface which varies between the extreme positions W and W as shown in FIG. 2. Also, as the wire is pulled from the circular guide element or guide rail 10 to a fixed feed position for the wire-drawing frame, it describes a generally conical path or generated surface W' which remains relatively constant. From the positions or surfaces generated by the wire between the extreme lines W and W", it will be clearly recognized that the running wire never comes in contact with the run-off flange 7.

Most importantly, a smooth and trouble-free unspooling of the wire takes place through the pinching or clamping action of the collar 4 resting on the guide rail 10 as indicated in FIG. 3. Thus, at any point of time, the running wire follows a path which forms a triangle between the run-off point of the spool winding 9, the braking point between the guide rail 10 and the collar 4, and the entry or feed point 2 into the wire-drawing frame as defined by the apex of the conical surface generated by the upwardly and inwardly nmning wire W (compare FIGS. 1 and 2). In moving through this triangular pattern, the wire itself moves simultaneously in two directions. The first direction of movement coincides with the axis of the wire itself. The second direction of movement takes place transversely to the wire axis and tangentially around the outer circumference of the guide rail 10 or the inner circumference of the collar 4. The braking of the wire between the guide rail and the collar should delay the second of these designated wire movements so strongly that the length of wire, which is located at any point of time between the run-off point on the outer layer of the coil 9 and the braking point, is tightly gripped or held in place. In this manner, the uppermost coil or layer of the winding also remains tightly wound or securely held onto the underlying layers of coil up to the moment of its actual removal from the spool. Thus, with the braking action of the collar in accordance with the invention, there is no tendency for the uppermost coil of the spool winding to become tangled or displaced during the unspooling operation, and a disturbance-free removal of the wire from the feed spool is guaranteed.

The desired braking effect of the invention is essentially obtained during the circular movement of the wire around the guide rail by means of the circumferential frictional pressure applied by the collar. The tension produced solely by the linear or axial direction of movement of the wire itself over the guide rail is not sufiicient to prevent a tangling or dislocation of the coiled wire on the spool, and such tangling or dislocation of several loops or coils immediately preceding the take-off point on the spool cannot be prevented if the collar is omitted. In this respect, the use of a slightly conically tapered collar on the runoff side of the guide rail is especially useful in providing a satisfactory braking and tensioning of the wire, and slight modifications in the shape or design of this collar can be readily accomplished in order to achieve almost any desired braking effect.

Since the foregoing description is directed to a single preferred embodiment of the invention, it will be recognized that one skilled in this art can readily provide other adaptations or equivalent structural elements which fall within the spirit and scope of this invention as set forth in the appended claims.

The invention is hereby claimed as follows:

1. Apparatus for the overhead unspooling of wire coiled on a flanged feed spool comprising: means for braking said wire during its run-off from the spool over the flange at the free end of the spool, said braking means including (a) a rounded, smooth-surfaced circular guide element mounted concentrically on the free end of the spool and extending at least partly past the run-off flange into an annular region which lies radially outwardly of the spool portion on which the wire is coiled, the diameter of said circular guide element being sufliciently greater than the diameter of said run-off flange to permit the wire to be pulled off said spool outwardly around said guide element in running and sliding contact therewith and then inwardly over the free end of the spool, and

(b) collar means composed of an elastomeric, abrasionresistant plasticized polyvinyl chloride coaxial with and supported externally of the spool and resting on the outer portion of said circular guide element for application of a braking pressure on said wire as it runs between said collar means and said circular guide element.

2. Apparatus for the overhead unspooling of wire coiled on a flanged feed spool comprising: means for braking said wire during its run-01f from the spool over the flange at the free end of the spool, said braking means including (a) a rounded, smooth-surfaced circular guide element mounted concentrically on the free end of the spool and extending at least partly past the run-ofl flange into an annular region which lies radially outwardly of the spool portion on which the wire is coiled, the diameter of said circular guide element being sufficiently greater than the diameter of said run-01f flange to permit the wire to be pulled off said spool outwardly around said guide element in running and sliding contact therewith and then inwardly over the free end of the spool, and

(b) collar means composed of an elastomeric, abrasion-resistant material coaxial with and supported externally of the spool and resting on the outer portion of said circular guide element for application of a braking pressure on said wire as it runs between said collar means and said circular guide element, said collar means having a substantially cylindrical portion tangential to and concentric with the outer diameter of said circular guide element and an inwardly tapering portion resting on the rounded surface of said circular guide element immediately adjacent its outer diameter.

3. Apparatus as claimed in claim 2 wherein said circular guide element is an annular rail having a substantially circular cross-section.

4. Apparatus as claimed in claim 2 wherein said collar is composed of plasticized polyvinyl chloride.

5. Apparatus as claimed in claim 2 in combination with a wire-drawing device having means to pull said wire from said spool over the run-0E flange to a feed guide point located approximately in the axis of the spool at a spaced distance from the free end thereof.

References Cited UNITED STATES PATENTS 2,338,539 1/1944 Quinlan 242-128 2,425,525 8/1947 Franz 242--128 3,389,875 6/1968 Brown 242128 LEONARD D. CHRISTIAN, Primary Examiner U.S. Cl. X.R. 242-l56.l 

